This recipe is only made with a shortening crust. Butter overwhelms the raspberries. Shortening offers the function of fat with the flavor of butter, so a lovely lilting fruit like the raspberry can shine.
Preheat the oven to 425 degrees.
Roll out the chilled bottom crust to 1/8-inch thickness. It should be about 13 inches in diameter. Place in a pie pan and trim the edges so there is no more than ¼ inch of overhang. Lift and crimp the overhang along the rim of the pie pan. Chill the bottom crust in the refrigerator or freezer.
Pick through the raspberries for any moldy ones. Put in a bowl with the sugar, salt, lemon zest and juice, and thickener. Pull out your top crust and roll it out for a lattice top. You should achieve the same thickness as the bottom crust.
Whip up your egg or get your cream in a bowl. Gently wash the top of the crust with a pastry brush. (It's OK if it gets on the fruit. This wash does not affect the flavor of the filling; it just adds a great crunch and depth to the top crust.) Sprinkle evenly with the raw sugar.
Create an aluminum foil barrier and place atop the pie. You want it to shield the crust from the heat, but you do not want to press the foil down upon the crust because it will stick to it and come up with the foil when you remove it.
Bake the pie for 30 minutes. Then, carefully remove the foil, rotate the pie 180 degrees, and reduce the oven temperature to 350 degrees for 30 minutes. The pie is done when you can see that the bottom crust is golden, about 1 hour total. Remove from the oven and let cool for 2 hours.